The headgear comprises ear cups (100a, 100b, fig 1a) and an air outlet nozzle positioned in front of a wearer’s face (1300, fig 1). Each ear cup 1100 comprises a housing containing a filter assembly 1112 and a motor-driven impeller 1109 for creating an airflow through the filter assembly to an air outlet downstream from the filter assembly. The ear cup further comprises an acoustic driver 1105 mounted to the housing, an inner acoustic microphone or vibration sensor 1106 disposed within the housing and an outer acoustic microphone or vibration sensor 1108 sensor mounted to the housing. The ear cup further comprises active feedforward noise control circuitry (fig 4a) that simultaneously uses the signals provided by the inner and outer microphones. A further microphone 1132 acts to provide a feedback error signal (fig 4a). Other microphone arrangements are described (figs 5 & 7).
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